1. Field of the Invention
The present invention relates to a rolling element retainer, and more particularly to a rolling element retainer which is applied to linear transmission device, wherein the linear transmission is applied to mechanical, electronic, automatic or semiconductor equipments.
2. Description of the Prior Arts
Conventional rolling element retainer can generally be divided into two categories: the first type of rolling element retainer is a single independent unit; the second type of rolling element retainer is comprised of plural independent units. Referring first to FIG. 11, wherein a slide block is slidably mounted onto a rail, the slide block is interiorly provided with rolling elements 30, between the rolling elements 30 is defined with plural single independent retainers 40 for preventing collisions of the rolling elements 30 with each other. In assembly, it is very time-consuming for the workers because they have to sequentially assemble the respective rolling members and the single independent retainers one by one into the slide block. Furthermore, the single independent retainers need to be tightly contacted the rolling elements, otherwise, the respective single retainers are susceptible to disengaging from the rolling elements at both sides, such that the circulation path will be jammed. But if the contact is too tight, which will lead to a bigger friction between the retainers and the rolling elements.
Referring again to FIG. 12, which shows a rolling element retainer comprised of plural independent units, wherein the rolling element retainer 41 includes plural partitions 411 which are connected with a flexible chain 412, so as to allow respective rolling elements 30 to rotatably receive in intervals between the respective partitions 411. Such kind of retainer 41 is produced by initially putting the rolling elements into mould, and then processed with plastic ejection molding, however, the requirement on the quality of the plastic material and the performance of the ejection molding machine is very strict, and thus the cost is relatively increased. Furthermore, due to the special manufacturing methods, the contact between the rolling elements and the partitions is kind of tight, which will result in a big rolling friction, accordingly the cornering ability of this kind of rolling element retainer is limited. The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional rolling element retainer.